In March 2014 I was a team lead for a small networking team in an Angolan ISP. After 5 years contributing the best I could to get the company of it’s feet, the time was coming for the progression many wished in their professional careers. I was invited to be the head of IT. Niiice!!! Continue reading
From very early in my networking career I have been fascinated by protocol details, packet captures and the features of my top 3 application troubleshooting tool: Wireshark.
Getting the captures on the endpoints (clients/servers) is relatively easy but things can get difficult when you want to capture traffic somewhere in between and is hard to do port mirroring (SPAN) on some remote switch.
Packet Capture Capabilities of Cisco Routers and Switches is an old video (4 years is old right?) posted on the Cisco Support Forums that highlights different methods to get on box packet captures in Wireshark .pcap format or in text output.
KRACK is the short name for an attack to the WPA (Wi-Fi Protected Access) security protocol, both WPA1 and WPA2. The vulnerability allows Wi-Fi traffic to be decrypted withouth knowledge of any keys even when using “secure” encryption like WPA2 (personal or enterprise).Continue reading
On April 11th 2017, well on the edge and on the last day before the old CCNA DC exams expiring I finally gog my CCNA Data Center certification, more than a year after starting the studies.
Was it hard? Yes, but no so much for the content.
My studies of Cisco Data Center technologies have led me to Cisco UCS (Unified Computing Systems). To manage a UCS domain Cisco provides us with the UCS Manager software. This software runs on switch-like devices called Fabric Interconnects acting as the “doorways” between the UCS domain and “the world”.
For all of us studying and needing to understand it without access to a bunch of expensive servers, Cisco was kind enough to create the UCSPE (UCS Platform Emulator) as a free downloadable virtual machine.
Since I’m not a good friend of VMWare and can’t have a bare metal hypervisor, my “playing” focuses mostly on Virtualbox but there is a small detail that must be taken care of:
Problem: After importing the UCSPE appliance you can’t access the GUI even after changing adapter 1 to Host-only or Bridge. Continue reading
Cisco announced last week a refresh of the CCNA Data Center and CCNP Data Center certifications. The new versions of the exams bring some changes to align content with what is more relevant today. I’m studying for CCNA DC and liked the changes… but I will keep studying since I have until April 11th 2017 to pass any of the “old” exams. Continue reading
If you’ve been in IT and networking in the last 5 years, you definitely know the 1st family of Cisco ISR (Integrated Service Routers) 1800, 2800 and 3800. If that’s true, you also seen the transition to ISR G2 (1900, 2900 and 3900) and felt the frustration of the new licensing model.
What does this have to do with the title?
Lately (15 years?) Cisco has been introducing new routers working with new operating systems:
- ASR 1000 running IOS XE in the enterprise edge and aggregation
- ASR 9000 running IOS XR in the Service Provider core and edge
- Nexus switches running NX-OS in the Data Center
All of these new OS’s are modular and bring only advantages when compared to the old IOS (Internetwork Operating System).
ISR 4000’s are no longer running IOS but IOS XE. ASR 9000 – recommended for the replacement of 7600’s – runs IOS XR. 2960 and 4500 switches have left IOS and have been running IOS XR for some years now.
This trend clearly shows us that the well known “classic” and monolithic IOS we came to love and hate since the 90’s is coming to an end. After these announcements, there are very few that still run “pure” IOS.
Is there a reason to worry?
No. Fortunately, NX-OS and especially IOS XE is keeping syntax and CLI (Command Line Interface) similarities with the original IOS. The notable differences are underneath in software architecture (Linux Kernel), modularity, memory protection and high availability. Only IOS XR has big differences but you can get the hang of it quickly with a few month’s practice (have a look at XRv)
You want to know a bit more?
Difference between IOS, IOS XE and IOS XR
Cisco ASR 1000 Series Aggregation Services Routers Software Configuration Guide: Software Packaging and Architecture
It’s a Friday afternoon, Friday the 13th actually, but the scenario has nothing to do with bad luck. In “Ilha de Luanda” (Luanda island), sitting by the sea, feeling the breeze and listening to the relaxing sound of the waves and a “fresh one” very close by, I came to meet Hudson Cruz…